Efficacy of computer-based voice output communicaton intervention in persons with chronic severe aphasia

Date

2003-05

Journal Title

Journal ISSN

Volume Title

Publisher

Texas Tech University

Abstract

The purpose of this study was to evaluate the efficacy of a Computer-Based Voice Output Communication System (CBVOCS) in a group of individuals with either global or severe Broca's aphasia. Additionally, this study collected data on the social validity of CBVOCS intervention from participants and other stakeholders. Specifically, nine individuals with severe Broca's or global aphasia (six females and three males) and a male individual with no intelligible expressive speech as a consequence of a brainstem stroke participated in this study. All participants with aphasia had incurred left hemisphere damage according to history, referral, and/or participant questionnaire, and were at least 12 months post onset before the beginning of this investigation. The participants ranged in age from 32 to 86 years. Minimal criteria for participating in this study included the ability to select symbols by activating the touch screen and adequate visual and hearing skills as determined by their ability to consistently select correct picture symbols in response to verbal stimuli. Materials included laptop computers with touch screens and speech synthesizers, Gus software program, and graphic symbols. The Gus software program was loaded onto each of the laptop computers, thus turning those computers into CBVOCS. The touch screens were selected primarily to provide easy access for participants with right hemiplegia, and secondarily to simulate access techniques used in most of the commercially available dedicated communication devices (e.g., Dynavox, Vanguard, etc.). A customized graphic symbol communication program was developed for each participant based on the vocabulary and topics of interest information obtained from caregivers via a questionnaire. In addition to the questionnaire, three scales were administered before and after intervention to assess changes in perception on variables such as communicative behavior and quality of life. A fourth scale was administered to the participants and caregivers after CBVOCS intervention to assess whether they experienced overall satisfaction with the program, and whether the CBVOCS intervention program employed acceptable treatment goals and procedures. The experimental procedure involved two phases. Phase I involved teaching the participant how to turn on the device, access symbols, and construct sentences of varying levels of complexity (i.e.. Level 1 [e.g., hold balloon] was the easiest level and Level 5 [e.g., The boy eats and the man cooks] was the hardest level). Phase II involved evaluating efficacy of CBVOCS intervention using preselected topics. The CBVOCS customized program was designed for each participant based on information obtained from the questionnaires and the participant's performance on Phase I. The customized program also varied across participants depending on the sensory, motor, and linguistic capabilities of the participant. Data obtained were analyzed separately for the following dependent variables: communicative effectiveness, mode of communication, and scales that were administered before and after CBVOCS intervention. Results indicated that the most frequently used mode of communication was CBVOCS followed by verbal, nonverbal, and vocalization. Additionally, most of the communication attempts across modes were effective more than ineffective. Across modes, higher effective responses were obtained for CBVOCS than for other modes of communication. Social validity of the results was assessed by analyzing ratings of change in communicative behavior as well as change in quality of life by participants and caregivers. Although statistically significant differences between pre and post CBVOCS intervention on social validity measures were not observed, the descriptive analysis of the data indicated a trend toward perception of improvement as a result of CBVOCS intervention. In summary, the results indicate that individuals with severe Broca's or global aphasia can learn to effectively use a customized CBVOCS program to enhance their communicative abilities.

Description

Keywords

People with disabilities -- Communication Aids, Communication -- Technological aspects, Aphasia -- Treatment

Citation